1. Field of the Invention
The present invention relates generally to a fan rotor mechanism, and more particularly to a fan rotor mechanism, which has high universality and is manufactured at much lower cost.
2. Description of the Related Art
Along with the miniaturization and high-performance development of electronic products, the requirement for heat dissipation has become higher and higher. Therefore, with the development of the electronic products, the heat dissipation technique has been improved to enhance the heat dissipation performance. A cooling fan has the advantages of low cost, mature technique, etc. so that various cooling fans are widely applied to the electronic products as heat dissipation devices.
FIGS. 1A and 1B show a conventional fan rotor mechanism including a case 10, a fan impeller 11 and a magnetic component 12. The fan impeller 11 has a receiving space 110 for receiving therein the case 10. The magnetic component 12 is annularly disposed along the inner circumference of the case 10.
According to the structural design of the conventional fan rotor mechanism, the size of the case 10 is varied with the change of the size of the magnetic component 12 annularly disposed along the inner circumference of the case 10. That is, in the case that the magnetic component 12 has a smaller size, the case 21 will have to have a smaller size in conformity with the size of the magnetic component 12 so that the magnetic component 12 can be tightly and securely assembled with the inner circumference of the case 10 by press fit. Reversely, in the case that the magnetic component 12 has a larger size, the case 21 will have to have a larger size in conformity with the size of the magnetic component 12 so that the magnetic component 12 can be tightly and securely assembled with the case 10. Therefore, it is necessary to manufacture different sizes of molds for different sizes of cases 10 in accordance with different sizes of magnetic components 12. This leads to increase of the manufacturing cost.
According to the above, the conventional fan rotor mechanism has the following shortcomings:    1. It is necessary to manufacture different sizes of molds for different sizes of cases so that the manufacturing cost is increased.    2. The universality of the conventional fan rotor mechanism is relatively poor.
It is therefore tried by the applicant to provide a fan rotor mechanism, which can be more universally used and is manufactured at much lower cost to eliminate the shortcomings of the conventional fan rotor mechanism.